Internet & Networking Basics in Java
Learn how the internet works — IP addresses, DNS, TCP/IP, ports, packets, and the OSI model in the context of backend Java services.
What Is the Internet
Before learning HTTP or APIs, it is important to understand what the internet actually is.
1. Internet as a Network of Networks
How the internet is structured.
2. Purpose of the Internet
Why the internet exists.
Computers on the Internet
Every device on the internet must be uniquely identifiable.
1. IP Addresses
Unique identifiers for devices.
2. Ports
How multiple services run on one machine.
Domain Names & DNS
Humans use domain names, but computers communicate using IP addresses.
1. Domain Names
Readable names for servers.
2. DNS Resolution
Converting domain names to IP addresses.
Data Transfer Over the Internet
Data is broken down and transmitted across networks.
1. Data Packets
How data is split and sent.
2. Latency and Reliability
Why speed and reliability vary.
HTTP and HTTPS Overview
HTTP is the foundation of web-based backend communication.
1. Role of HTTP
Why HTTP exists.
2. HTTPS and Security
Why HTTPS is essential.
How Requests Reach a Backend
Understanding this path helps debug real-world backend issues.
1. Request Journey
Steps from client to server.
2. Intermediate Systems
Systems between client and backend.